While dumbbell or barbell curls focus on flexing the biceps through a full range of motion, drag curls change the game by ...

Stand with your feet shoulder-width apart, holding a barbell with an underhand grip. Keep your elbows tucked at your sides ...

you should be able to load up the barbell and go a lot heavier than you would doing a regular bicep curl. If you don't want to stray too far from your regular dumbbell curls, the hammer curl is an ...